Manager as a resource integrator

Recently, I kept asking myself what is a manager's role? Upon introspection and multiple readings, I have been able to firm up my opinion that a Manager is in fact a resource integrator. Though different jobs have different resources and require quite different integration skills but almost all managers mainly act as resource integrator in their day to day lives.

However, the way a manager integrates resources highlights manager's job effectiveness. In my opinion, there exists 3 kind of managers. First, who just integrate resources to achieve desired results. Nothing more, nothing less. Such managers fall in "MANAGE" buckets.

Second, who integrate resources with the aim to gain optimum utilization. These managers fall in "OPTIMIZE" bucket.

Lastly, their exists managers who aim to improve the overall efficiency. These managers fall in "IMPROVE" bucket.

I think, based upon one's management experience and type of project/task - a manager can fall in any of these categories. Imagine a project manager managing multiple projects - where he might fall in "IMPROVE" bucket for one project but would fall in "MANAGE" bucket for another project.